Unlock instant, AI-driven research and patent intelligence for your innovation.

Nitride based semiconductor light emitting device

a technology of nitride and light emitting device, which is applied in the direction of semiconductor devices, basic electric elements, electrical apparatus, etc., can solve the problems of nm or less significantly poor bending of energy band, etc., and achieves reduced internal electric field, enhanced luminous efficiency of nitride based semiconductor light emitting device, and decreased difference

Active Publication Date: 2013-11-14
KOREA PHOTONICS TECH INST
View PDF1 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The present invention enhances the luminous efficiency of nitride based semiconductor light emitting devices by forming a strain control layer in the quantum well layer of the active layer. This reduces the internal electric field and increases the recombination probability of electrons and holes involved in a light-emitting process, resulting in an increased recombination rate and enhanced luminous efficiency.

Problems solved by technology

A nitride based semiconductor light emitting device (also referred to as an ultraviolet light emitting device) that emits ultraviolet light with emitting wavelength of 365 nm or less has significantly poor luminous efficiency in comparison with other nitride based semiconductor light emitting devices having other wavelength.
Unfortunately, in an AlGaN / AlGaInN multi quantum well structure used as a light-emitting layer, a bending of energy band is caused by a difference in lattice constant between the quantum barrier layer of AlGaN and the quantum well layer of AlGaInN.
Therefore, the number of electrons and holes involved in a light-emitting process is reduced, and the luminous efficiency of the ultraviolet light emitting device is deteriorated.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Nitride based semiconductor light emitting device
  • Nitride based semiconductor light emitting device
  • Nitride based semiconductor light emitting device

Examples

Experimental program
Comparison scheme
Effect test

first embodiment

[0017]FIG. 1 is a cross-sectional view illustrating a nitride based semiconductor light emitting device having an active layer with an interposed strain control layer in accordance with the present invention.

[0018]FIG. 2 is a diagram illustrating an energy band gap of a nitride based semiconductor light emitting device having an active layer with an interposed strain control layer in accordance with the first embodiment of the present invention.

[0019]FIG. 3 is a diagram illustrating an energy band gap of a conventional nitride based semiconductor light emitting device.

second embodiment

[0020]FIG. 4 is a diagram illustrating an energy band gap of a nitride based semiconductor light emitting device having an active layer with several interposed strain control layers in accordance with the present invention.

[0021]FIG. 5 is a PL (photoluminescence) spectrum, measured at room temperature, of a nitride based semiconductor light emitting device having an active layer with an interposed strain control layer in accordance with the first embodiment of the present invention.

MODE FOR CARRYING OUT THE INVENTION

[0022]The following descriptions are provided to assist in a comprehensive understanding of an embodiment of the present invention. Well known techniques, elements, structures, and processes will be omitted to avoid obscuring the subject matter of the present invention.

[0023]Particular terms may be defined to describe the invention in the best manner. Accordingly, the meaning of specific terms or words used in the specification and the claims should not be limited to the...

2nd embodiment

2nd Embodiment

[0042]Although the nitride based semiconductor light emitting device 100 in the first embodiment uses a single-layered strain control layer 43 as shown in FIG. 2, this is exemplary only and not to be considered as a limitation. Alternatively, as shown in FIG. 4, a strain control layer 140 may be formed as multiple layers.

[0043]Referring to FIG. 4, the nitride based semiconductor light emitting device in the second embodiment has a structure that the strain control layer 143 is formed as multiple layers in the active layer 140. In this case, a plurality of strain control layers 143 may be formed to have the same or different energy band gaps (w3, w4).

[0044]The maximum energy band gap (w3) of the plurality of strain control layers 143 is between that the energy band gap of a quantum barrier layer 142 and the energy band gap of a quantum well layer 144. The minimum energy band gap (w4) of the plurality of strain control layers 143 may be the same as or smaller than the en...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The disclosure relates to a nitride based semiconductor light emitting device with improved luminescence efficiency by increasing a recombination rate of electrons and holes contributing to luminescence, which results from matching the spatial distribution of electron and hole wave functions. The nitride based semiconductor light emitting device according to the present invention includes an n-type nitride layer, an active layer formed on the n-type nitride layer, and a p-type nitride layer formed on the active layer. At this stage, a strain control layer, and the at least one layer has a larger energy bandgap than a quantum well layer in the active layer. The strain control layer is disposed in an area where the quantum well layer of the active layer is formed. Moreover, an energy bandgap of the strain control layer is less than that of quantum barrier of the active layer.

Description

TECHNICAL FIELD[0001]The present invention relates to a nitride based semiconductor light emitting device and, more particularly, to a nitride based semiconductor light emitting device in which at least one strain control layer having an energy band gap greater than that of a quantum well layer of an active layer is formed in the quantum well layer in order to enhance the luminous efficiency by reducing an internal electric field.BACKGROUND ART[0002]Normally a nitride based semiconductor light emitting device has a stack structure of a buffer layer, an n-type semiconductor layer, an active layer, a p-type semiconductor layer and an electrode on a substrate. The active layer is a region where electrons and holes are recombined, and has a structure that a quantum well layer is disposed between quantum barrier layers. Depending on kinds of material forming the active layer, the emitting wavelength of the nitride based semiconductor light emitting device is determined.[0003]A single qua...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H01L33/12H01L33/04
CPCH01L33/12H01L33/04H01L33/06H01L33/14H01L33/32
Inventor JEON, SEONG RANSONG, YOUNG HOKIM, JAE BUMKIM, YOUNG WOOCHEON, WOO YOUNGKIM, JIN HONG
Owner KOREA PHOTONICS TECH INST